The science of attachment parenting

"Attachment parenting," or AP, is an approach to child-rearing intended to forge
strong, secure attachments
between parents and children.

For many parents, this approach feels intuitive. And anthropological
research suggests that practices associated with AP -- such as
baby-wearing and co-sleeping -- have deep roots in our evolutionary past
(Konner 2005).

But does AP contribute to better child outcomes?

Not surprisingly, it depends on your definition of "attachment parenting."

If we use the definition first proposed by William and Martha Sears, then "attachment parenting" is essentially another term for "sensitive, responsive parenting."

The Searses suggest a list of principles and practices that go along with AP (see below), but they have stressed that it isn't necessary for parents to follow all of them. The practices are intended to help care-givers achieve the goals of being sensitive and responsive to children. Parents can experiment, and see what works.

A similar approach has been taken by Attachment Parenting International. As this organization states on its website, parents should "take what works and leave the rest."

This is the definition I will address here, and, as we will see, there is a large body of research indicating that sensitive, responsive parenting benefits children.

Among other things, it appears to protect children from the effects of toxic stress -- helping children develop resilience in the face of adversity. It may also reduce a child's risk of developing behavior problems, and promote the development of moral reasoning (see below).

If we focus on specific practices, the evidence is mixed. In general, the practices recommended by the Sears are beneficial. But not every practice works for everyone, and not every claim (made by various advocates) has been supported. For instance, baby-wearing has benefits, but it doesn't appear to stop colicky babies from crying excessively.

So evidence in favor of "sensitive, responsive parenting" doesn't tell us that every associated practice is the best choice for a family. If we want to know the effects of a specific practice, we need controlled studies that target that particular practice.

What about other definitions of attachment parenting?

It's important that other conceptions of attachment parenting are not consistent with what we know about effective care-giving behavior. They also may be rooted in pseudo-science beliefs about the biology of motherhood.

For example, according to one writer, attachment parenting means responding immediately to a crying infant by offering a breast; "waking every hour" at night to feed; or rushing in with pre-emptive attempts to soothe, so that parents fail to find out what their babies actually need (e.g., Jenner 2014).

This isn't the sort of behavior that has been linked with secure attachments. And it's inconsistent with what researchers mean by "sensitive, responsive parenting."

To fit the researcher's criteria for "sensitive and responsive," a parent needs to accurately interpret the baby's signals, and provide an appropriate response. That's not what this definition describes, and all that rushing to intervene can be counter-productive.

For instance, babies often make noises during brief moments of waking during the night. They may also vocalize when they are sleeping. If parents misinterpret these sounds and rush to feed a baby, they are needlessly depriving everyone of sleep -- and perhaps teaching the baby to awaken frequently at night!

So if we define "attachment parenting" as a kind of frenetic attempt to deliver fast responses (including unnecessary intrusions that prevent babies from developing patterns of consolidated, nighttime sleep), we have little reason to think this would benefit families.

The same may be said for definitions that require parents to adopt an extremely child-centered lifestyle -- the sort that leaves parents feeling overwhelmed, unsupported, and socially isolated from other adults.

Not only is this bad for a parent's mental health, the popular rationale for this lifestyle appears to be rooted in fairy tale beliefs about what's "natural," like the idea that human mothers evolved to be intensive, exclusive providers of parental care.

The implication is mothers are designed to devote all their energies to child-rearing, and thrive doing so. It's the ancestral way. If a mother can't manage it -- or doesn't enjoy it -- something is wrong.

Anthropological research refutes these notions. If there are any peoples whose life-ways most closely resemble those of our ancestors, it is the world's last remaining hunter-gatherers. Yet hunter-gatherer mothers don't devote all their energies to child-rearing.

Yes, they have child care duties, but they have other work as well, and they raise their children with the help of relatives and friends.

In some of these societies, as much of half the daytime care of infants is contributed by other relatives -- like fathers, siblings, grandmothers (Konner 2010; Hrdy 2009; Hrdy 1999). Even in societies where hunter-gatherer mothers provide the majority of infant care, parenting bears little resemblance to the fairy tale scenario of "total motherhood." When coping with a crying infant, mothers nearly always receive some sort of help -- either with soothing the infant, or with some other aspect of infant care (Kruger and Konner 2010).

So it's easy to find problems with "attachment parenting" if we define it differently than the Sears have.

In the remainder of this article, I will ignore alternative definitions, and focus on reviewing the evidence favoring physical closeness, sensitivity, and responsiveness in parents. For information about books, websites, and organizations that offer support to parents committed to these principles, click here.

Attachment parenting in its original formulation: What does it look like?

According to William and Martha Sears, attachment parenting is associated with a range of practices and approaches, including

But William and Martha Sears, who coined the term "attachment parenting"--note that there is no checklist of specific practices that parents must follow (Sears and Sears 2001).

What's important, argues these authors, is that parents strive to be sensitive and responsive -- so that they can learn how to meet their children's needs in an affectionate, effective way.

This is not the same as being overly-protective. By definition, securely-attached kids are not overly-clingy or helpless. They are the kids who feel confident to explore the world on their own. They can do this because they trust that their parents will be there for them (Mercer 2006).

And if we take the Sears's definition to heart -- if attachment parenting is synonymous with "sensitive, responsive parenting" -- then it follows that attachment parenting will look different from one family to the next.

What's the scientific case for attachment parenting?

Some
writers have attempted to support these claims with studies of
extremely deprived infants (both human and nonhuman). For instance,
research demonstrates that kids who are terribly neglected and
abused—like children raised in the infamous Romanian orphanages—suffer
neurocognitive impairment and socio-emotional problems (Chugani et al
2001).

While such research confirms that chronic stress and
trauma are bad for the brain, it's a stretch to cite these studies as
proof that attachment parenting is superior to "mainstream" Western
parenting. As a result, some critics have argued that the attachment
parenting movement is based on overblown or fallacious claims (Hayes
1998; Warner 2006).

This is unfortunate, because there is a lot of
scientific evidence supporting the idea that secure attachments and
attachment parenting practices benefit kids. Here's a sample.

Links between attachment parenting practices and secure attachment

Several aspects of responsive parenting have been associated with the development of secure attachments.

These include:

High-quality communication. A study of Dogon mothers in Mali found that
the quality of communication between mother and infant was associated
with more secure attachment relationships (True et al 2001).

Maternal sensitivity during infant play. A study of premature infants
reports that infants whose mothers were unresponsive or more controlling
during playtime were more likely to be insecurely-attached (Fuertes et
al 2006). Securely-attached infants were more likely to have mothers who
were sensitive to their childrens' interests and needs (Fuertes et al
2006).

Insight into a child's mental and
emotional states. A study of mothers and their 12 month old infants
reports that mothers who showed greater insight about their babies' psychological experiences were rated as more sensitive and were more
likely to have securely-attached infants (Koren-Karie 2002). Another
study reports that mothers who showed a more accurate understanding of
their infants' mental states at 6 months were more likely to have
securely-attached infants at 12 months (Meins et al 2001). Read more about these links here.

Sensitivity to an infant's distress. A study analyzing data
collected by National Institute of Child Health and Human Development
(NICHD) reports that American mothers who showed greater sensitivity to
their infants' distress at 6 months were more likely to have securely
attached toddlers at 15 months (McElwain and Booth-Laforce 2006). By contrast, infants are more likely to develop insecure attachments when mothers "close up their faces" -- looking away from the baby, and failing to respond with sympathetic facial expressions (Beebe and Steele 2013).

Baby-wearing. An experimental study randomly assigned American mothers
of low socioeconomic status to either wear their newborns in soft baby
carriers or to carry their babies in portable infant seats. At 13
months, babies in the soft-carrier group were more likely to be
securely-attached to their mothers (Anisfeld et al 1990).

Emotional availability. Research suggests a link between secure
attachment and emotional availability—being open to discuss emotions,
and being ready to respond sensitively and appropriately to the emotions
of others (Easterbrooks et al 2000). An Israeli study observed mothers
interacting with their infants and found that moms rated as more
emotionally available were more likely to have securely attached
children (Ziv et al 2000).

How secure attachments and responsive parenting practices benefit children

In addition, infants are less likely to develop fearful tendencies if their mothers show higher levels of emotional sensitivity and responsiveness during parent-child interactions (Gartstein et al 2017).

When researchers tracked 45 mother-child pairs from
infancy to age 7, they found that infants who were securely-attached
during infancy were more likely to demonstrate emotional availability at
age 7 (Easterbrooks et al 2000).

Why? Secure attachments may be intrinsically helpful, but it's also likely that specific parenting characteristics play a role.

For instance, in a study of American children (aged 9-11 years), researchers found that kids with secure
attachment relationships--and greater levels of maternal support--showed "higher levels of positive mood, more constructive coping, and better
regulation of emotion in the classroom." (Kerns et al 2007).

Another study found that parents who were responsive to their children's distress had kids who were better at regulating their own, negative emotions. In addition, children showed an improved ability to regulate their positive emotions if their mothers showed higher levels of warmth (Davidov and Grusec 1996).

Attachment parenting practices buffer children from the effects of toxic stress

As I note in this article about stress in babies, there is a lot we can do to keep babies calm and happy. It's true for older children too. But do these things make a big difference? I think they so, particularly for children who are very sensitive, emotionally reactive, anxious, or exposed to high levels of environmental stress.

For example, there is compelling evidence that skin-to-skin contact benefits young infants.

In one study comparing two groups of preterm infants, researchers found that children who'd received skin-to-skin contact in the first weeks postpartum had developed, by age 10, more healthy stress response systems, improved sleep patterns, and better cognitive control (Feldman et al 2014).

In another recent study, newborns at high risk for developing abnormal stress responses showed no evidence of such problems at 7 months -- not if their mothers reported giving their babies lots of caresses (Sharp et al 2012).

Co-sleeping may also reduce stress. Researchers have reported that British children (aged 3-8) who slept in their parents’ rooms showed lower daily levels of the stress hormone cortisol (Waynforth 2007). In a study of Dutch infants, co-sleeping babies experienced lower spikes in the stress hormone cortisol when they were subjected to psychologically distressing situations (Beijers et al 2013). And an experiment testing newborns' responses to bathing found that, compared to co-sleepers, babies who slept alone experienced sharper spikes in cortisol levels (Tollenaar et al 2012).

But perhaps the most dramatic evidence comes from research that measures emotional sensitivity and responsiveness. As I note in this article, people who grow up in poverty experience high levels of stress, and may therefore be at high risk of developing stress-related diseases, atherosclerosis, autoimmune disorders, and cancer. But studies suggest that kids who have highly nurturing parents are protected from these risks.

The advantage may begin early in life. One study reports that infants of more sensitive mothers had lower baseline levels of the stress hormone cortisol (Blair et al 2006). Other research, which I discuss in this blog post, suggests that babies with "difficult" temperaments may turn into particularly well-adjusted kids if they receive warm, sensitive parenting (Stright et al 2008; Pluess and Belsky 2010).

And recently, researchers have found evidence that warm, sensitive parenting protects young children from brain-shrinking stress. Joan Luby and her colleagues found that poverty-stressed kids with warm, positive, emotionally-supportive parents had better brain development. Unlike peers with less sensitive parents, these kids developed normal-sized hippocampi and amygdale—brain structures that play a key role in spatial learning, memory consolidation, stress reactivity, and the processing of emotion (Luby et al 2013).

Finally, positive discipline may help kids cope better with stress. One study of kids living in highly-stressed urban settings found that parents who identified themselves as practitioners of positive discipline were more likely to have children who were stress-resilient (Wyman et al 1991).

Evidence that sensitive, responsive care reduces behavior problems

Observational studies show that securely-attached children are less likely to develop behavior problems (Madigan et al 2015). Likewise, observational research indicates that children have better behavioral outcomes when they receive sensitive, responsive parenting.

For instance, a longitudinal study tracking the development of 544
babies found that children with more sensitive mothers were less likely
to experience executive function problems (including problems with
attention, focus, and impulse control) when they were four years old
(Kok et al 2013).

These links are suggestive, but not conclusive. Some children suffer from conditions that put them at higher risk for both behavior problems and difficulties forming attachment relationships. And maternal sensitivity is partly influenced by genes -- genes mothers share with their children (Cents et al 2014).

What if these "maternal sensitivity" genes have the additional, independent effect of making it easier for children to develop strong executive function skills? We can't jump to conclusions about causation.

But controlled experiments help clarify matters, and support the idea that sensitive, responsive parenting can have a direct effect on behavior problems.

Some examples:

One experimental study reports that children living in stressed families (characterized by marital conflict and frequent daily hassles) showed fewer overactive problem behaviors if their parents had been trained in positive parenting and sensitive discipline techniques (van Zeijl et al 2006).

A study of foster children found these kids developed better cognitive flexibility and perspective-taking skills if their caregivers had been trained to "follow the child's lead" by delivering sensitive, responsive, nurturing care (Lewis-Morrarty 2013).

And when researchers taught parents how to improve their emotional coaching skills, kids experienced fewer behavior problems at school (Havighurst et al 2013).

You might have heard that breastfeeding boosts a child’s IQ-—if, like 90% of the population, he carries the FADS2 gene (Caspi et al 2007). That result wasn't replicated by a subsequent study, so the jury is still out (Steer et al 2010).

One possibility is that breastfeeding is really just a marker of other parental behaviors and favorable environmental factors. For instance, breast-feeding mothers tend to be better educated and more affluent.

Another possibility is that the benefits of breastfeeding depend on the precise content of breast milk -- that only milk with higher levels of DHA fatty acid (docosahexaenoic acid) confers special effects on cognitive ability (Bernard et al 2017).

But while we wait for more research to clear these matters up, there are hints secure attachments are linked with higher intellectual achievement.

For example, a British study of 36 middle-class mothers and their three-year-olds found that securely-attached children scored 12 points higher on the Stanford-Binet intelligence test than did insecurely attached children (Crandell and Hobson 1999).

Another study tracking 108 French-Canadian children found that kids who were securely-attached at age 6 scored higher on communication, cognitive engagement, and motivation to master new skills at age 8 (Moss et al 1998).

Of course, correlation doesn't prove causation. It might be that smarter kids have an easier time forming secure attachments.

But there are also experimental studies that suggest a causal link between attachment parenting practices and intelligence, at least in children who would otherwise be at risk. In these experiments, some mothers were randomly assigned to receive training in responsive parenting techniques. Afterwards, the infants of trained mothers showed greater growth in cognitive skills than did the infants of control moms (Landry et al 2003; 2006).

Warm, flexible, sensitive communication contributes to a child's moral development

Do attachment parenting behaviors promote cooperation and moral reasoning? There's reason to think so. In a study that followed children throughout early childhood, toddlers who engaged in mutually responsive, positive interactions with their mothers had more developed consciences when they reach school age. These children were also more likely to comply with adult instructions (Kochanska and Murray 2000).

And research has found links between responsive parenting and empathy. Kids with more responsive mothers tend to show more empathy and prosocial behavior towards others (Davidov and Grusec 1996).

Is it the communication that really matters in these cases? Or are the links simply a reflection of something else -- like a shared genetic tendency to be sensitive and cooperative?

As with all developmental phenomenon, a child's moral reasoning is affected by an interaction of genetic and environmental influences. But research supports our intuitions on this point: Kids are affected by our behavior, and benefit when we tailor our responses to fit their personalities.

For instance, in a study tracking children from the age of two, researchers noticed that sensitive mothers used different tactics depending on their children's temperaments, and these adjustments predicted higher levels of moral reasoning at age five.

In particular, children with exuberant, outgoing temperaments turned out better if their mothers responded to toddler misbehavior by using redirection and distraction. These kids also responded well to gentle but firm prohibitions about what they shouldn't do. Reasoning with them was less effective.

By contrast, the use of commands was unhelpful for children with fearful or inhibited temperaments. They responded better to reasoning (Augustine and Stifter 2015).

Results like these underscore why it's counter-productive to define attachment parenting as a set of required practices.

In its original formulation, "attachment parenting" is another name for being sensitive and responsive. By definition, that means responding to each child on a case-by-case, individual basis. A practice that seems to work well with some children might be unsuitable for others.

Unproven claims and unanswered questions

Baby-wearing and crying

As noted above, baby-wearing may be associated with higher rates of secure attachment. It also may help prevent plagiocephaly, the flattening of the back of the head caused by leaving babies on their backs for extended periods (Littlefield 2003).

But does baby-wearing reduce crying?

Intuitively, it seems that it should. However, with the exception of one study conducted in 1986 (Hunziger and Barr 1986), there isn’t much scientific evidence to support the idea. For example, a 1995 study reports that “supplemental carrying" of infants had little effect on crying rates (St James-Roberts et al 1995). Possibly, results depend on the temperament of the individual infant. For an overview of research about crying, see this Parenting Science guide.

"Mind-mindedness"...the crucial factor?

"Mind-minded" parents treat their children--no matter how young-- as individuals with minds, feelings, thoughts, and beliefs of their own.

Psychologist Elizabeth Meins and her colleagues have shown that mind-minded parenting is linked with with the development of stronger empathy and perspective-taking skills in children.

It's also linked with more secure attachment relationships. In one longitudinal study, mind-minded parenting at 6 months was correlated with more secure attachments at 12 months. Indeed, mind-minded parenting was a better predictor of secure attachment than were any other variables, including "responsive, sensitive parenting" (Meins et al 2001).

This makes me wonder. Is mind-mindedness the true foundation of attachment parenting? For more information, check out this article.

References: Attachment parenting

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carrying promote attachment? An experimental study of the effects of
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Beijers R, Riksen-Walraven JM, and de Weerth C. 2012. Cortisol regulation in 12-month-old human infants: associations with the infants' early history of breastfeeding and co-sleeping. Stress. 16(3):267-77.

Hays, Sharon (1998). The Fallacious
Assumptions and Unrealistic Prescriptions of Attachment Theory: A
Comment on "Parents' Socioemotional Investment in Children Journal of
Marriage and the Family 60 (3):782-790.

Warner, Judith. 2005. Perfect Madness: Motherhood in the Age of Anxiety. Riverhead.

Waynforth
D. 2007. The influence of parent-infant cosleeping, nursing, and
childcare on cortisol and SIgA immunity in a sample of British children.
Dev Psychobiol. 49(6):640-8.

Wyman PA, Cowen EL, Work WC,
and Parker GR. 1991. Developmental and family milieu correlates of
resilience in urban children who have experienced major life stress.Am J
Community Psychol. 19(3):405-26.